W-6F

W-6F is a three-way, three-element full range speaker, all LF, MF and HF are front horn loaded. The enclosure is a bass reflex vented design. For a 3-way full range speaker system, it is very compact having very good size to sound pressure ratio. As compare to W-3F, it has a wider dispersion angle, 60 o (H) X 40 o (V) and the low frequency extended even lower.

Enclosure

• High frequency horn is specifically designed for W-6F with a special opening and geometry to make it a constant directivity of 60 o (H) X 40 o (V) (See Figure 36)
• The MF horn is also specifically designed for W-6F. It coupled to a 10-inch driver producing very smooth response (See Figure 37)
• The front radiation of the LF unit is horn loaded and the back radiation is bass reflex (See Figure 38)

At a given sound pressure, this design can reduce the vibration amplitude of the LF unit therefore reduce amplitude distortion especially in frequency band near the lower limit.

The enclosure can be made very compact. The shape of the enclosure is trapezoidal for easier arraying

(4) The enclosure is made of 18mm (11-ply) birch plywood. All joints are tenon and mortise of Chinese tradition plus screws and adhesive to ensure the rigidity and durability.

Many domestic and imported speaker enclosures using medium density fibre (MDF) board to reduce cost, but MDF has a fatal weakness. It soften when moisten and loss its rigidity. IBO rather uses expensive birch plywood to build the enclosures to ensure its strength and rigidity no matter used indoor or outdoor, rain or fine.

The enclosure is heavily braced internally and a black powder-coated perforated steel mesh grille protects the drivers from damage. The finishing is in black semi-matt textured environmental friendly paint. A rear connector plate fitted with two Neutrik Speakon NL4MP connectors for amplifiers and for loop-in and loop-out to additional enclosures. (See Figure 39)

See Figure 39

The Component

The LF unit of W-6F is L15/100/06Z

L15/100/06Z is developed by iBO specifically for horn loading

• Frame is die cast alloy
• The cone is a special formula of pulp and glass fiber. The depth of the cone is rather shallower with reinforcement ribs for better reproduction of low-frequency
• Surround and spider are stiffer to increase the mechanical stiffness
• The cone is treated with inflammation resistant agent
• The diameter of the voice coil is 4-inch edge wound with flat copper wire on a Kapton former.
• The magnet is made from y30 high flux strontium ferrite weights 8.54kgs.

(see Figures 40 and 41)

Figures 40

Figures 41

MF unit is a M10/75/02Z 10-ih driver specifically developed for W-6F.

• Designed operating range is 250HZ to 2KHZ, low to mid frequency crossover point of W-6F is 300HZ, mid to high is 1.8KHZ, well within operating range
• The materials of the cone is specially formulated pulp, mica and carbon fiber and the depth of the cone is a little shallow as it does not need to cover a wide operating range. The cone is very light in weight but very rigid
• The phase plug is specially designed and optimized for the coupling of M10/75/02Z and the loading horn.

Without the phase plug, the radiation from the center of the diaphragm or cone and the radiation from of the edge reach the throat at different time as the distances are different, and phase different occurred (See Figure 42).

Figure 42

With the phase plug in place, the radiations from the center and from the edge are traveling at equal distance. When these radiations reach the throat, they are in phase.

The diameter of M10/75/02Z’s voice coil ois 3-inch and is edge wound with flat aluminum wire on a Kapton former(see Figure 43)

Figure 43

• Magnet is made from y30 high flux strontium ferrite. The magnetic structure weights 7.00kgs. (See Figure 44)

Figure 44

HF unit is a H3/75/03Z

The H3/75/03Z is developed by iBO featuring:

• The diaphragm is made of titanium and its surround is Mylar. The voice coil is edge wound with feat afumimium wire, (See Figure 11 and 12) the diameter is 3-inch (75mm)
• The diameter of the throat is 1.4-inch (35mm)
• The slits pattern of the phase plug is circumferential.
• y30 high flux strontium ferrite is employed and the magnetic structure weights 6.05kgs.

. (See Figure 45, 46 and 47)

Figure 45Figure 46 Figure 47

The experiential horn was chosen due to its minimal changing rate of cross section.

We expect the acoustic impedance of a horn be kept constant pure resistance for a widest possible frequency band. Exponential horn fulfilled this requirement. The materials of the horn is fiberglass reinforced plastic.

Crossover Network

The sensitivity of W-6F’s high frequency component (108 dB w/m) is much higher than the low frequency component (99 dB w/m). The difference is more than 9 dB. If a build-in passive crossover network is employed, the sensitivity of W-3F can only be 99 dB w/m. It does not make sense to sacrifice the 9 dB of the high frequency component. Besides, any passive crossover network have an insertion loss. The actual sensitivity of W-6F would be less than 99 dB w/m. We decided not to employ passive crossover network for W-6F and recommend using external speaker processors that incorporate delay and equalization functions such as iBO D026(2 IN 6 OUT) digital speaker processors.

Applications and Technical Specifications

Maximum (not the peak) SPL of a single W-6F is 132dB (HF), 131dB (LF). Several W-6F or mixed with W-3F and/or W-8F plus subwoofer W-218B to form a 3-way or 4-way array enough to handle any large scale activities such as large touring, large concert, arenas and stadiums, large theaters etc., suitable for either indoor or outdoor.

Technical Specifications and diagrams (See below)

Rigging

Chick here for product W-6F